Tuowei Fm
Type Locality and Naming
It was named by The Six team of Yunnan Geological Bureau in 1980. The named section is located near Tuowei village, Shede Township, Qiubei County, Yunnan Province.
Synonym: Tuwei Fm (spelling)
Lithology and Thickness
It is composed of carbonate rocks, divided into two members: Lower part of Bottom member is gray, thick layer dolomite and dolomite limestone, the upper part is gray banded and medium thick layer cryptocrystalline limestone with thin layer dolomite, with thickness of 901 m. Upper member of this formation is composed of gray, thick layer to blocky bioclastic limestone with banded limestone and is 1043 m thick.
Relationships and Distribution
Lower contact
It is in conformity with the underlying Gejiu Fm of the lower Middle Triassic. The layered dolomite at top of Gejiu Formation is taken as the boundary.
Upper contact
It is in conformity with the overlying Niaoge Formation of the Upper Triassic. The top is marked by the disappearance of thick bioclastic limestone.
Regional extent
They are distributed in Qiubei, Shizong and Gejiu of Yunnan Province. The lithology is relatively stable and with large thickness variation. At Tangzibian village - Tangfang village, the lower member is more than 1422 m, while the upper member is only 765 m.
GeoJSON
Fossils
The fossils are rare and only found bivalves such as Asoelia illyrica, Piagiostoma costata, and the brachiopod Rhaetina anegustaformis.
Age
Depositional setting
Tuowei Formation is saline shallow water sediment.
Additional Information